A storage device includes a switching unit which switches an access destination in a storage area between a first storage area and a second storage area in response to an access request from a host device; and a nonvolatile storage medium which stores a first host device information used to identify the host device in the second storage area, and a software module executed by a CPU provided in the host device, the software module comprising causing the an authority grant unit which transmits a control signal for switching the access destination to the first storage area to the switching unit of the storage device, when the acquired first and second host device information are compared to find that the first and second host device information match with each other.